arm64/mm: enable ARCH_HAS_VM_GET_PAGE_PROT

This defines and exports a platform specific custom vm_get_page_prot() via
subscribing ARCH_HAS_VM_GET_PAGE_PROT. It localizes arch_vm_get_page_prot()
and moves it near vm_get_page_prot().

Link: https://lkml.kernel.org/r/20220414062125.609297-4-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Anshuman Khandual 2022-04-28 23:16:13 -07:00 committed by akpm
parent 634093c59a
commit b3aca728fb
3 changed files with 26 additions and 24 deletions

View File

@ -45,6 +45,7 @@ config ARM64
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_VM_GET_PAGE_PROT
select ARCH_HAS_ZONE_DMA_SET if EXPERT
select ARCH_HAVE_ELF_PROT
select ARCH_HAVE_NMI_SAFE_CMPXCHG

View File

@ -35,30 +35,6 @@ static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags)
}
#define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags)
static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags)
{
pteval_t prot = 0;
if (vm_flags & VM_ARM64_BTI)
prot |= PTE_GP;
/*
* There are two conditions required for returning a Normal Tagged
* memory type: (1) the user requested it via PROT_MTE passed to
* mmap() or mprotect() and (2) the corresponding vma supports MTE. We
* register (1) as VM_MTE in the vma->vm_flags and (2) as
* VM_MTE_ALLOWED. Note that the latter can only be set during the
* mmap() call since mprotect() does not accept MAP_* flags.
* Checking for VM_MTE only is sufficient since arch_validate_flags()
* does not permit (VM_MTE & !VM_MTE_ALLOWED).
*/
if (vm_flags & VM_MTE)
prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED);
return __pgprot(prot);
}
#define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags)
static inline bool arch_validate_prot(unsigned long prot,
unsigned long addr __always_unused)
{

View File

@ -55,3 +55,28 @@ static int __init adjust_protection_map(void)
return 0;
}
arch_initcall(adjust_protection_map);
pgprot_t vm_get_page_prot(unsigned long vm_flags)
{
pteval_t prot = pgprot_val(protection_map[vm_flags &
(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]);
if (vm_flags & VM_ARM64_BTI)
prot |= PTE_GP;
/*
* There are two conditions required for returning a Normal Tagged
* memory type: (1) the user requested it via PROT_MTE passed to
* mmap() or mprotect() and (2) the corresponding vma supports MTE. We
* register (1) as VM_MTE in the vma->vm_flags and (2) as
* VM_MTE_ALLOWED. Note that the latter can only be set during the
* mmap() call since mprotect() does not accept MAP_* flags.
* Checking for VM_MTE only is sufficient since arch_validate_flags()
* does not permit (VM_MTE & !VM_MTE_ALLOWED).
*/
if (vm_flags & VM_MTE)
prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED);
return __pgprot(prot);
}
EXPORT_SYMBOL(vm_get_page_prot);